The following countries have lower average IQs than that of the US (which is 98):I wondered where the heck this alleged data came from, so I searched on a subset of the list (what did we do before the net?). It turns out it's from a book called the IQ and the Wealth of Nations, evidently inspired by the notorious/famous/infamous "Bell Curve" book.
Canada 97 Czech Republic 97 Finland 97 ... Guinea 66 Zimbabwe 66 Congo (Zaire) 65 Sierra Leone 64 Ethiopia 63 Equatorial Guinea 59.
Hong Kong was #1 on the full list, but one could argue it's too small and atypical for this sort of ranking. South Korea was #2 and perhaps deserves pride of primacy (Despite being a euro I have some strong familial bonds to SK, so I'll claim a sort of secondary pride. One amusing correction: the web page links from SK to an article on the IQ benefits of learning Chinese characters -- which kind of misses the point that one of Korea's most brilliant inventions was a phonetic script that led to widespread literacy.)
So is there anything to this ranking? I'm skeptical of both the quality of the data and the agenda of this web site, but from what we know of the impact of malnutrition and intrauterine stress I would expect many of the world's most poor nations to be at the bottom of an "honest" list. The lesson here is that we we need to couple interventions to improve nutrition and reduce disease burden to the economic interventions critical to reducing poverty.